1. Field of the Invention
This invention relates to a child resistant closure. More particularly, it concerns a closure which can be converted from a child resistant to a non-child resistant configuration. While in its child resistant configuration, this closure provides an obstacle to a child attempting to remove the closure from a container. After conversion to a non-child resistant configuration, the closure may be readily removed.
2. Description of the Prior Art
Many types of child resistant closures are known in the art. Their common objective is to provide a closure that is too difficult for small children to open, yet easily opened by adults. While many child resistant closures effectively prevent child access, they also present a problem for adults who lack the manual dexterity or strength to remove the closures. This commonly arises in the case of people suffering from arthritis.
This problem was addressed in U.S. Pat. No. 4,406,376, which discloses a snap on closure which when installed in a first position is child resistant, but when reversed is easily removed by adults. This was not, however, readily adaptable to closures which are rotatably engaged upon containers.
U.S. Pat. No. 4,731,512 also addressed this problem in the context of a rotatably engaged closure. However, the disclosed closure system requires an external instrument when used by adults who lack the manual dexterity or strength required to operate the closure and even then still requires pressure be applied to the external cap.
U.S. Pat. No. RE29,779 discloses a child resistant container using a reversible cap which uses a snap action to open and close the closure.